Object 1 starts at 5.4m and moves with a velocity of 1.3m/s. Object 2 starts at 8.1m and moves with a velocity of -2.2m/s. At what time will these two objects collide. * PLEASE A GOOD ANSWER. IM NEED HELP RN

Point charges q1=+2.00μc and q2=−2.00μc are placed at adjacent corners of a square for which the length of each side is 1.50 cm . point a is at the center of the square, and point b is at the empty corner closest to q2. take the electric potential to be zero at a distance far from both charges. part a what is the electric potential at point a due to q1 and q2? express your answer with the appropriate units.